Enduring dirt and shame is an ancient conception of virtue.
Tips
usage
垢 appears in several set expressions: 藏污纳垢 (to harbor criminals; a hotbed of vice), 含垢忍辱 (to endure humiliation and disgrace). As a standalone noun, it means physical dirt or grime.
土 (the earth radical) is the literal substance - dirt, grime, soil. It anchors 垢 in the most concrete sense of filth (caked-on dirt) and from there extends to the figurative shame and disgrace of 含垢 'swallowing dirt' or 蒙垢 'covered in shame'.
后 supplies the sound, shifted to gòu. The same phonetic crops up in 诟 (gòu, revile) and 逅 (hòu, encounter), making the gòu reading a tight little subfamily - and revile-and-grime go hand in hand semantically.
